This invention relates to cyclone separators and particularly to the separators of the type used with grain transporting equipment.
Such apparatus generally comprises a fan for developing a first airstream upstream of the fan for collecting the particulate material and a second airstream downstream of the fan for transporting the collected particulate material along a duct to a separate location. Such apparatus are generally used for removing the material from a grain bin to place it in a truck for transport or vice versa and are particularly useful for collecting the last small amounts of the grain which cannot be transported by an auger.
In order to prevent the grain and other particulate material from passing through the fan, the grain is separated from the airstream passing into the fan by a cyclone separator. The clean air then passes from the separator through the fan and picks up the separated grain from the bottom of the separator through an airlock for transportation along the duct.
The cyclone separator generally comprises an outer container which has a cylindrical portion and an inner cylinder coaxial therewith so as to define an annular space between the two cylinders. The air and particulate material is injected into the annular space substantially tangentially thereto so that the air and particulate material swirls around the annular space with the particulate material falling to the bottom of the container and the air exiting through the bottom of the inner cylinder to an outlet at the top of the inner cylinder. However, these cyclone separators operate unsatisfactorily with some types of particulate material particularly small seeds such as sunflower seeds which do not have sufficient mass to be readily separated from the air and tend therefore to be transported to the fan. In addition such cyclone separators have a severe problem in that if a blockage occurs in the duct the separated material builds up in the separator until the material is drawn through the outlet to the fan thus blocking the whole system and requiring a major overall to release the blockage.